Flame-retardant compositions are generally applied to the surfaces of materials, such as fabrics and laminates. The flame-retardant materials may be liquids or may be applied as solutions in a solvent or emulsified in a liquid. The liquids are usually sprayed on the substrate to be rendered flame-resistant or padded on from rolls. The flame-retardant may also be forced into pores and interstices of the substrate under pressure so that the flame-retardant occupies pores and cracks within the substance of the substrate, such as disclosed in U.S. Pat. No. 4,223,066. In the presence of heat or flame, the flame-retardants usually undergo chemical reaction or physical change to render the substrate flame-resistant. Polymers or resins are also often used to aid in adhering the flame-resistant material to the substrate.
The principal problem which often causes surface coating of substrates to be deficient in rendering the substrates flame-retardant is the tendency of most surface coatings to washing off of the substrates under conditions of cleaning or laundering. After a few cleanings, a surface coated flame retardant most often washes away to leave a fabric or laminate thus coated unprotected against flame or heat. Use of resinous materials, adhesives, and other such ingredients usually only delays wash removal of the flame-retardant material or causes it to break away from the substrate when under heat.
The present invention provides a permanently incorporated flame-retardant material into the structure of a laminate so that cleaning and applied heat or flame have no effect on its permanence in the substrate.